1. Field of the Invention
The invention relates to an electrical circuit arrangement with concentrated elements in multi-layer substrates. The invention relates further to a filter, which contains the electrical circuit arrangement.
2. Related Technology
Conventionally, capacitors are realized in circuits as concentrated, discrete components. Accordingly, a high precision of the component tolerances and a reasonable manufacturing cost can be achieved. However, the resulting capacitors occupy a large space and do not always fulfill the requirements for symmetry in an optimum manner. One approach to resolving these problems is the use of integrated capacitors.
For example, DE 195 40 570 A1 discloses an integrated capacitor with a finger structure in a printed circuit board. In this context, two comb-shaped structures interlock with one another on one layer. However, the resulting capacitor is limited in its capacitance value. Furthermore, it requires a large area.
Filter structures with discrete components are conventionally manufactured on printed circuit boards. This generates a large space requirement. Furthermore, the filters are not necessarily adequately symmetrical as a result of the structure of the printed circuit board and the individual components. Through the use of ceramic substrates with integrated inductances and capacitors, the space requirement can be reduced.
Accordingly, US 2005/0200431 A1 discloses a filter on a ceramic multi-layer substrate, which realizes inductances directly as strip conductors on the layers of the substrate. In this manner, it is possible to achieve a reduced space requirement by comparison with printed circuit boards. However, a compensation of production-process-determined tolerances is not achieved. Because of the small dimensions of the strip conductors applied to the levels of the multi-layer substrate, even small displacements of the substrate layers relative to one another have large impacts.